The present invention relates to a data storage cartridge for storing disc player-readable data on a media. More particularly, it relates to a disc cartridge having a restraining or locking mechanism for securing a disc within the disc cartridge when the disc is not in use.
Data storage cartridges are universally accepted devices for distributing, storing and accessing large volumes of data. In its most basic form, a data storage cartridge is comprised of an outer shell which maintains and protects a disc or disc substrate. Typically, the shell includes a sliding door through which the disc is accessed. The disc substrate can assume different forms, such as a magnetic disc or an optical data disc. Regardless of specific media type, the disc substrate will receive and/or store data accessible/readable by a disc player. This data can assume a wide variety of forms, such as CAD, games, spread sheets, music, word processing, etc.
To access data from or record information to a disc, the data storage cartridge is inserted into a disc drive. A conventional disc drive includes a drive spindle and head. The drive spindle engages the disc cartridge while a portion of the disc substrate is exposed to the head or disc reader. As the drive spindle rotates the disc within the shell, the head is able to "read" or "write" information to or from the disc substrate.
Technology associated with computers, and, in particular, data storage discs, has rapidly evolved. Optical discs have exponentially greater data storage capacities than previous media. Formats of optical data discs include audio CD (compact disc), CD-R (CD-Recordable), CD-ROM (CD-Read Only Memory), DVD (digital versatile disc or digital video disc) media, DVD-RAM (random access memory), various types of rewritable media, such as magneto-optical (MO) discs, and phase change optical discs. Even with the advancement of technology, however, the same general principles apply; namely, the disc cartridge is comprised of a shell surrounding a disc.
While technology associated with the actual disc media has evolved, the general configuration of the data storage cartridges has not. The standard data storage cartridge design is highly serviceable, but may present substantial quality control issues. In particular, while the shell serves to protect the disc from many potential hazards, nothing protects the disc from the shell itself. In other words, the shell virtually encompasses the disc and is preferably made of a hardened material. Thus, when the data storage cartridge is not in use, the shell protects the enclosed disc from possible damage due to scratching, oils, etc. normally encountered during handling. However, the disc may be relatively unconstrained within the shell. The disc can move in both an axial and radial direction. Thus, unless great care is taken when handling the data storage cartridge, abrupt movements of the data storage cartridge cause the disc to shift within the shell. The disc is free to strike the cover, base or sides of the shell. As the disc substrate is highly sensitive, these movements may cause damage to the disc. Further, movements of the disc inside the shell may also cause rattle sounds which compromises a user's perception of cartridge integrity and quality.
Attempts have been made to address the above-described problem. For example, known magnetic and optical disc cartridges include an arm that applies a radial restraining force against the outer diameter of the disc. Such a mechanism does not protect well against the up and down motion of the disc, which is a major source of disc rattle. Biasing the optical disc substrate along an outer edge of the disc into contact with a side wall of the shell may damage a portion of the formatted area of the substrate.
Further, some magnetic and optical data storage cartridge restraining mechanisms are activated when the cartridge door is closed and released when the cartridge door is open, allowing for the disc to flop and rattle in the cartridge when the user opens the door under handling. Once the disc cartridge is placed within a disc drive, the shell sliding door is opened, disengaging the restraining mechanism. In this condition, when the drive spindle is not engaged with the disc, the disc substrate may rattle and/or even dislocate the disc significantly within the shell due to vibrations and shock seen by the disc drive. Further, with a drive mounted on its side, once the cartridge sliding door is open, the now-released disc substrate is free to fall to one side, possibly compromising disc alignment and disc surface integrity.
It is desirable to have a locking mechanism for securing and protecting a disc when the disc is not in use, without damaging the integrity of the data located on the disc. It is desirable to have a data storage cartridge having a locking mechanism which restrains movement of the disc in a direction perpendicular to the data surface and also in a radial direction. It is desirable to have a data storage cartridge including a locking mechanism which, when located within a side mounted drive, prevents the disc from flopping to one side. Further, there is a need for a disc cartridge having a locking mechanism which inherently provides for tight sealing of the disc data surface from error and debris flow when the data storage cartridge is not engaged with the disc player drive spindle. Therefore, a substantial need exists for a disc cartridge having an locking mechanism for securing and protecting the disc when not in use.